Aftermarket whirlpool kits

Any recommendations on installing an aftermarket whirlpool kit to an existing garden tub. Pro’s, con’s, or products to use? I found a company called Convert-A-Tub that offers a kit for around $300. Anyone ever use them?

I purchased and installed the Convert-A-Tub 6 jet kit. I had a few tricky decisions to make and the installation took a little longer than they advertise, but the end results are very nice. The kit comes with everything you need except the hole saws.