My Rail rattles quite noticeably but tbh it doesn’t bother me anymore. The quality of the ride and ability of the bike far outweighs the annoying rattling.
I invisiframed my Rail as soon as I got it, it’s surprisingly easy if you just follow the instructions, even around the suspension parts and strangely therapeutic if you’ve got a spare few hours. You can hardly tell it’s on unless you know where you’re looking.
It took me a couple of rides to get used to my Rail 7 coming from a 130mm travel trail bike. I noticed exactly what you described. You can plough through anything and maintain more speed. The 29” wheels have never been an issue at my local trails either. I don’t think I’d go back to 27.5.
I haven’t been contacted but it’s becoming more and more common. I’d advise everyone with a gen 4 motor to check the nut and mark it so you can see if it is becoming loose.
If the PF5 has Gen 4 motor The 625 will fit. I have a Rail with 625 battery and the wife’s PF5 has a 500, both batteries work in both bikes. Both with Gen4 motors.
To use a proper tool yeah you have to remove the crank arm. You can use a hammer and punch but I’d not recommend it. You’d most likely damage the nut and you’ve no way of knowing the torque it’s tightened to.
i had to tighten mine and a was surprised how tight 30nm was when it was on the stand, ideally you need to have 3 arms, two to hold the torque wrench and one to hold the none drive side crank. I’ve only had the bike out once since I torqued it back up, 20 miles ish, and it’s not budged.