Any beard and moustache trimmer will do for any long body hair anywhere - there isn't much difference I can see between the cheap under $20 ones and the expensive over $60 ones.
But there are two types of trimmers. Those on electric shavers like on my Phillips have the two trimming blades with teeth exactly aligned to get a close trim of sideburn lines. You could easily nick yourself with this type of trimmer. Most, however, have one trimmer blade and its teeth set back slightly from the other - so you can't get as close a cut as with my Phillips - but you won't be a mass of nicks either.
Whether you then want to use electric or blade for the final close shave (if you can be bothered) is up to you.