I have read a few of the threads around about fenders but was wondering if those clamp on mudguards/fenders like the ones Topeak sells:

https://www.topeak.com/products/fender_lead.html

are universal fit or fit on a 3700? and do they work well? are fenders worth it or just plain cheesy?

I had thought about getting a seatpost clamp rear rack and bag also...should I just tiewrap a piece of plastic under the rack instead of a rear fender?

I am just going to be doing trail riding and riding to work (road/sidewalk)

Thanks

If you're going to be trail riding and commuting. Get full coverage. There's no sense going for partial coverage fenders if you got the eyelets for them.

They won't be of any use to you when it's sunny and nice on the road, but when it's even damp with small puddles, you'll be glad you had them.

Do you have eyelets for a rack too? Or are you restricted to seatpost racks?