Which épée blade should I buy next, and is a maraging (FIE) blade worth the extra cost?
A maraging blade is worth it if you will fence events run under FIE rules, or if you fence hard and often enough to break regular blades; otherwise a good non-FIE blade from a mainstream fencing brand is completely fine. Maraging steel is a high-strength alloy with a lot of nickel and cobalt plus molybdenum and titanium, hardened by a long ageing heat treatment, which is where the name comes from. The FIE specification asks for steel with a high resistance to breaking and low susceptibility to rust, and each approved blade model must be rechecked every two years to keep its FIE approval.
The FIE makes maraging blades compulsory in all three weapons at its events, and USA Fencing confirms this has applied to every weapon at FIE events since September 2021. The push came after the 1982 World Championships, where Soviet champion Vladimir Smirnov died when a broken blade went through his mask. Blades less likely to break were part of the safety overhaul that followed, along with stronger masks and clothing. USA Fencing's domestic rules do not require maraging blades, so regular blades are accepted at US local, regional and national tournaments.
Maraging blades still break; they are built to resist the fatigue cracks that eventually snap a blade, so they generally break less often. For someone fencing four or five times a week, a blade that lasts longer can make up for part of the higher price. For a once-a-week fencer, or a kid who is still growing into a longer blade size, the regular blade is usually the better buy. Either way, the guard, grip and pommel move to the next blade, so you are only ever replacing the blade.
Within either family, choose on feel. Stiffness matters most: medium is easier to flick, stiff gives better point control and holds its shape. Balance comes from the whole weapon, so a heavier guard or grip moves weight back toward your hand while light point parts reduce tip heaviness. Tell the seller which grip you use, since French grips need a long tang. Buy your main and spare blades the same so switching mid-bout feels identical, and borrow club mates' épées for a few bouts before deciding.