Yes it works.for me personally a pillow is too much elevation, its more comfortable to use a folded towel or just tiltmy pelvis myself. Its about finding the right angle of penetration. All girls are going to be set up a little differently down there so its hard to say what will work for your specific partnerbut if you experiment a little you should be able to find something that works
I've never put a pillow underneath me in missionary..
Why don't you try while in the missionary position, take one of her legs and put it over your shoulder, gets in deeper, and when she's comfortable with that, take her other leg and have both over your shoulder.
there are several positions that are very good for gspot..first you gotta learn the anatomy of girls..her gspot is 2-3 in inside her p****y..on the area close to her belly button..so when she's layind on her back..its on the "cieling" of her vagina...once you know where it is..you know what to aim for...
1.doggy stye is generally known to be best..BUT DONT LET HE PUT HER FACE DWN ON THE PILLOW..you want her to have her legs together[this makes her tighter]..with her back arched and her ass up..her on all fours without putting her face down..
2.her on her back with her legs either over your shoulder...her feet on your chest..or you holding her by the ankles and her legs in a "V"...
3.HER ON TOP...but leaning kinda back..so your penis is directly hitting her gspot..so instead of her doing the usualy cowgirl..make her lean back and ride you..
4.stick your fingers inside her..and do a "come here" motion with your fingers..about 2-3in inside..you would feel a soft,fleshy,wrinkled area..this is her gspot..the hornier she gets the bigegr her gspot gets..