If you are going to use the t-5 lights just for clones, you might not need the 4' light. I can cover two trays, 50 per tray with the 4' light until the first transplant. Depending on your available space you may want to consider the 2' length. If your in it for the long haul the t-5's are a good investment.
If you have two or more branches that you can cut from the bottom of your plants its time to clone, especially if your doing it so you can start flowering the original plants. You will have one more opportunity to take cuttings from them. It will usually take about two weeks for them to start flowering when you change the light cycle. If you trim the bottom 1/3 of the plants at that time you wil have more clones if you want. Be aware that if you do this, all of the clones will be at about the same maturity. If you match the law of averages, you will have twice as many plants for your second grow, so get ready for them. VV