Solo I: Hill climbs and time trials. You reach higher speeds, but you need more safety equipment (suit, gloves, shoes, socks, SA helmet, baclava (facial hair), nomex underwear), roll bar/cage, SFI approved harnesses, fire suppression system, window nets OR arm restraints.

Also more chance of really crashing your car. I saw an Eclipse go off a cliff couple of years ago after a rain storm. That was ugly.

From there you could get into Club Racing which is on actual tracks going door to door.

But to say I'm really good is a bit too much I"m not up there just yet.