Purchased a set of irons 9 years ago with varied results. The heads ordered were copies of Callaway X20s. My opinion of Giga clubs is if you get what you pay for and dont expect any claims of game improvement. Here is a list of the issues I had with my set.
Chrome finish chipped easily
Decals came off within a year
Performance was sub-par when compaing 7 irons with the Callaway, 15 yard loss in the Giga.
8 iron head came loose and all ferrules changed position within a year.
Gigagolf —- Independent reviews are up and down. The forgings look good, but they have problems stocking. The player improvement irons have some quality control issues namely paint, decals, breakage
You cannot buy heads separately. You have to buy the entire club with a choice of 4 shafts.
Lie and length can be adjusted prior to ordering. These options are all available from Maltby. In a pinch would I buy from them? Probably not. You get what you pay for.