I like to do it because it can save a bit of money and time for me. If I order a batch online, I can pull the yeast out and get it started while my ingredients are on their way, so I don't have to wait to make my beer once I get the stuff.
Also, at 7 or 8 bucks a pop, I can re-use the same yeast several times before I have to get more as long as I keep it in good condition.
I love being as involved in the process as I can, and the only thig I don't do at this point is grow and malt my own barley. It's more about having a good time and enjoying the entire process than just getting beer for my.
As far as your lag time goes, I usualy use at least a 2 liter starter for all my beers, and this is especially important for a quick start in a lager which are slow movers anyway. I can get fermentation within an hour or two with a good starter, but I also can get a lag of a day or so, and have had lagers take almost two before. It really depends on what the yeasts feel like doing, and how well prepared everything was, but I am sure everything is fine. RDWHAHB