I have the Scosche Rhythm+, it's a light based monitor and if you read the reviews of the tech it is supposed to be more accurate than the electrical based ones. Given that all top athletes use the electrical based chest straps this may just be marketing, so read the reviews and make your own call. I like it other than the strap, it is falling apart and seems to be a flaw in the design, hopefully they fix it. I seem to get consistent results and being a data nerd its fun to look at how close to death I come on some climbs. I push 190 - 200 on big efforts early in rides, hr seems to smooth out to 130-160 regardless of effort as I get warmed up but it really spikes early in rides. It feels accurate but I have nothing to gauge against as I have never used a hr monitor before and have only been using this one for four months or so.