If diving is your thing then there is a strong case for Hurghada as the dive boats go out to the islands and offshore reefs. These are much less visited and are absolutely breath taking.
If it's a regular holiday, Sharm seems to be the best option. I've not been to Sharm but i understand it's more developed with more (and more refined) restaurant/nightlife options than H. Casual snorkelling off a beach is probably easier in Sharm too.
H is best placed for excursions to Luxor and The Nile (which is stunning).
I think excursions from Sharm go to places like Mt Sinai.
Haven't been in May, we went in winter (it's currently mid 20s celsius in Hurghada) but I expect it will be blinkin' hot.
Hope this helps. Enjoy.