Penny wise, pound foolish. I own Mares Volo's. I owned Apollo Bio Fins (split fins) before the Volo's. I have used Quattros and the cheaper Mares Plana Avanti. I also have a really old pair of Seaquest fins that are stiff plastic and cheap.
I do pool work, including swimming and snorkeling 800 yds. each. I have tried and timed various models. Here's a quick summary.
Mares Volo's - I can overkick them. Speed was always below others. Easy on the legs, so good for the out of shape diver. Good maneuverability. Same as Dacor Tigers. Dacor Panthers are a cheaper version of the pivot fin and can save you some money. I have well over a hundred dives on them, plus OW pool sessions, plus my daily pool workouts. The little pivots have not broken.
Apollo Bio Fins - Loved them, pricey like Volo's. Easy on the legs. Excellent speed. Not so good for surface swims. Harder to maneuver with. Can't back up, something I need for photography.
Mares Quattro's - My favorites. They really aren't that stiff. Best paddle fin out there. My best times were with my wife's Quattro's.
Mares Planta Avanti - Surprised at the performance for the money. Good for the budget minded.
Seaquest something or others - I couldn't do two laps without my foot cramping. They were too stiff to be comfortable. I couldn't even work them without a rocking motion. Couldn't finish my 800 yds.
CHEAP, ILL FITTING, POOR PERFORMING FINS WILL MAKE YOU MISERABLE. They cost you air consumption as well.
Check your sizing. Different brands have different foot pocket sizes. Some are wider than others. Some pockets will rub your instep raw. I would recommend any split fin or Mares/Dacor fins.
good luck