Comparing Flexeril vs Gabapentin. Flexeril has an average rating of 6.0 out of 10 from a total of 235 ratings on Drugs.com. 47% of reviewers reported a positive effect, while 28% reported a negative effect. Gabapentin has an average rating of 7.1 out of 10 from a total of 2463 ratings on Drugs.com.