Altera Stratix V FPGAs actually had more market share than Virtex 7s. They were better chips. That said, the production delays around Arria 10 and Stratix 10 and the time lag caused by the Intel acquisition totally killed their market position. The only reasons to use Intel FPGAs now are (1) 64-bit floating point support or (2) if your Intel salesman gives you a really good deal.