The biggest difference in the a1s and the a2s is in the amount of adjustability. The A1s only have 5 clicks for dampening controll. Other than that the consturction of the dampers is different as the A2s use a mono tube and the A1s do not.
For the money the A1s are an awesome street suspension. They are definately in the same league with the tein super street. Many would think that the most comparable damper would be the tein basic which is similar in price, but the basics do not have any dampening controll where as for just about the same price the JICs offer height adjustability and some degree of dampening controll.
They are definately a winner, and for the price they are tough to beat. The A2s are a set up that is going to stand up to street use and track use. They are for the more serious and competitive driver. As you can tell they cost a bit more and offer more adjustment.
Please let me know if you have any other questions. Just so you know we have sold several sets of A1s at this point and everyone that we have sold them to has been very happy. Please let me know if you have any additional questions of if there is anything else that we can do for you. I sincerely look forward to hearing from you again soon.