Bosch PerformanceLine CX motor and battery are awesome. Be sure the firmware is updated so that Sport mode activates eMTB mode. You can tell because when you toggle to Sport mode, "eMTB" will show up at the bottom of the display for a few seconds.
The Trek rear suspension design is great.
The only weak spec on that bike is that the fork is a little suspect for eMTB use. If you are less than say, 180lb, and don't ride gnarly trails, you'll be OK. If you are a heavy rider and/or ride rocky and rough terrain, the fork is going to let you down occasionally.
I don't want to be that guy, but I demoed that bike and wasn't impressed. Poor suspension, didn't like the 10-speed drivetrain, brakes were weak, no dropper seatpost, thin tires. We had a hardtail eMTB that same day and were swapping back and forth and I actually preferred the hardtail over the FS. I'm very familiar with the Bosch motor which is good, but the newer 2020 version will be better and lighter.
I got mine new at the beginning of this year and I love it.
Full suspension works great, tires are great and really dig in and climb.
I ride single track, fire roads and streets, all with the same tires.
I get over 40 miles per charge, never ran out yet, I don't let it get too low, I just charge it up before it's empty.
So far this year I've ridden over 3000 miles, averaging about two hours every day.
I would highly recommend this bike. I ride year round here in the Northeast.
Studded tires in winter & regular in summer.
The 2020 Trek Powerfly still have the older Gen 3 motor. No worries because the Gen 3 is a great motor, and reliable, but just be aware that going to a 2020 model bike doesn't necessarily get you the new motor. It's a different size so can't just be swapped out old for new. The frame has to be built for it.
The new Trek Rail looks awesome with the new Bosch motor:
I am riding a powerfly fs 7 and a 9.7. For most of my trail riding I like the fs 7 better because I think it is more responsive to the trail. I have a couple issues with it, weak brakes, uncomfortable seat, and the dropper post is marginal. The 9.7 is a big bike that is good on jump trails and technical downhills. My issues with this bike is the nx derailleurs that only shift one gear at a time. I usually only get 14-15 miles on a battery charge, but my trails are extremely rough and steep, too much for normal biking. Overall, I think these bikes are awesome and worth the cost.
The new Bosch Gen4 is smaller, lighter and works completely differently from the earlier Boach PerformanceLine motors. The previous generation had a 1:2.5 gearbox between the crank and the chainring. Every revolution of the crank turned the chainring 2.5 revolutions. This means in order to keep the gear ratios sane, the chainrings are tiny. Unfortunately, this causes several issues. To get the equivalent of a 34T front chainring with the Bosch Gen3, you would have to run a 14t chainring. The chainrings wear out really fast, and being so small causes a bunch of clearance problems with frame design.
The new Bosch Gen4 motor does not have the gear multiplication, so it uses standard cranks and chainrings.
The new Trek Rail has a 625Wh battery as well.
Reviews are just coming in on the Bosch Gen4 motor. All of the usual (paid) suspects say it is great, but time will tell.
Another advantage of the Gen4 is that there are new, and better displays, and they have Bluetooth connectivity so your phone can be used as a controller and stat gatherer.
I have not read whether you can do firmware updates with your phone like you can with the Shimano system. That is another shortcoming of the Bosch Gen3 system, firmware can only be updated by a dealer with the proper software and connector cables.
The Bosch Gen3 system, despite its deficiencies, works great, is extremely reliable, and has been the largest selling high-end mid-drive system for years. It is a little outdated compared to Gen4, Shimano, Brose, and the newer Yamaha motors.
Honestly, if the older bike is not significantly discounted, I would go with the newer system.
Well its official I bought a Powerfly FS 7 plus, for better or worse, Talked to the Rep of Trek found out their 625 watt batteries will fit the newer 2019's 7', which is my biggest concern, Somebody else will have to test new Bosch cx motor.
I have the 2017 Trek Powerfly 8 FS. only 130mm suspension f/b, but I changed air can in forks for 150mm travel up front. So I slide a little further up the seat nose to power up the steeps.
1500 miles thru a broken-humerus, knee replacement, and rotator-cuff repaired.
I'm 215 lbs. geared up. I run 2 tokens in fork, and all three possible in shock. Shock still not as poppy at forks. Rear suspension linkage seems a bit too linear for playful, but works well otherwise.
Downieville, Mills Peak, Mt. Hough, Northstar, Ashland, Post Canyon, & Black Rock are some of the areas we've ridden.
As long as I'm not in a bunny-hopping contest, its a BLAST! ;-)
I have 2000 miles on the Bosch CX and has been very reliable except for when a stick damaged the speed sensor wires ($40)
I went with the 14t chain ring to get adequate lower gearing.
The older Bosch CX small chain rings are murder on the chains so I suggest getting a chain gauge and replace the chain often.
If you let the chain go too long it will prematurely wear out the cluster
Does the eye-eye allow for swapping out for a coil over shock? Ever since I went over 200lbs I have been riding coil overs since rear air shocks just don't seem to like the pressures that are needed for heavier riders.