I'm not a fan of anything with random draw.
I like to know what my numbers are when I go pay. I don't run anything on anything I have to time and I'm not a fan of the races ran where I live now where you have to pay before the first horse runs and you draw number 200 or pre-enter and in the wintertime - I'm not pre-entering anything in Okla lol 

That being said: several of us built our own.
Works great! I can have a payout done within minutes and I never close the books.
edited to add: farmtec has an interface cable you can buy and it dumps the times in automaticly. The only time I touch the PC is when I have to put in a NT.
Have several hot keys built in to sort draw, sort by results and figure my payout. I still have to adjust before a race for a 4d,5d etc payout of course