I use warmshowers extensively when I tour and would recommend them wholeheartedly. I used to use couchsurfing but no longer bother.

Warmshowers consists of experienced bike tourists or people interested in doing so. The hosts I've had are always aware of my needs as a touring bicyclist, supportive, and kind people. There aren't all that many warmshowers host in the world and you may find it hard to locate one near where you want to stop. Also, I tour solo so have no experience finding hosts as a couple.

Couchsurfing used to be a good resource for finding hosts. It has a large number of members and some useful ways to search their database. But, couchsurfing doesn't cull their members in any way and most of their listings are out of date. The site tries to remedy this by sorting the results with the most "useful" first, but this doesn't really help much.

In the past, couchsurfing had a map you could bring up that showed where potential hosts were. Now, the search is, at its narrowest, within 5kms of a named city. What does it mean to be 5kms from a big city, say Rome or Los Angeles? On my last trip (just completed), I had one couchsurf lined up with someone who was 70 and responsive. I was looking forward to meeting him but he had to cancel at the last minute.

When I tour, I always check warmshowers first. If nothing is available, I look for a hotel. If the hotels are too expensive, I might check couchsurfing but lately, I haven't found the time I spent looking at the site to be useful. The response percentage at couchsurfing is far lower than warmshowers, in my experience.

Some basic information: I don't carry camping gear which would expand the places I could sleep (backyards, floors). I have enough money to rent a hotel whenever I want.

Since I don't camp, I need to find a place to sleep each night. As a result, I do extensive planning for my trips, including where I can stop each night and find a bed. I add in extra, unplanned, days for problems that arise during the ride. I look for places to visit, interesting places to rest and things to do on a rest day (one day in 5 for me), and I check for warmshowers hosting locations and route myself there if the hosts are available. I prefer this level of planning and feel it greatly enhances my touring experience.