I have both but can't use the DP attachment for it doesn't fit the DP. It's a King mortising set that cost $99 and is still brand new. It doesn't fit the collar on my General Intl DP. So I bought a dedicated mortiser a couple of years ago and I love it. The limitations only apply to a very small % if mortising requirements and if I ever need those I'll go old school and drill with a Forstner bit and chisel it square. My mortising machine is the Canadian version of HF, named Busy Bee. They sell a brand named Craftex and it's not high end but works fine and only $199 when I bought it. My joiner is also a Craftex.
Don't fear your tools, pay attention and respect the tools and avoid injury.