You don't "need" a rio skagit line, they are just easier for beginners to cast. I was told by numerous guys to get something in the windcutter length, (55 foot head) and learn the proper fundamentals of casting first before getting a skagit, which I did. The skagit is easier to cast and will let you get away with more mistakes..but as you get better you will be a running line stripping monkey and that is not fun...(see cut and calllous's on my fingers)
My advice is listen to what these guys say...Yes it's a bit more frustrating in the beginning but enjoy the journey, it will make you a better spey fisherman and it's a helluva lot more fun NOT stripping in a ton of line and just bringing in a little and ripping it back out...
P.S. If it says you need a cheater, get the cheater, otherwise you'll be pulling your anchor out of the water too soon and hooking yourself and tossing ugly loops.