How to choose a fitting toy?

I have used 1.4 and 1.5 inch diameter buttplugs, 1.5 wasn’t a comfortable process, or comfortable release. I read this [Aneros Choice Guide](http://letstalksex.net/buy-best-aneros-reviews-buying-guide/), I consider my self a beginner with some experience. from reviews it seems like Aneros toys functionality vary greatly person to person. I think the Progasm Jr is more for me than the MGX Classic according to reviews.
I’m not a tall guy- I’m 5’7″ so that may play into this? idk, but id appreciate help in singling out a toy. I’d be very thankful for your help.