Cavities and Dental Insurance

I have to get two cavities filled, but since I just started a new job my dental insurance won't kick in until May 1.  My dentist said the cavities will be fine for a month since they are pretty small.  One is on the bottom, the very last tooth on my right side, and is an old filling that's coming out.  I'm going to get tooth colored since you can see it.  The second cavity is on top right side, the very last tooth, and I'm going to get the cheaper filling because you can't see it.  

I believe I need a resin-based composite for the first and an amalgam for the second.  Is this correct?

The reason I ask is because with my new job, dental insurance is very expensive.  I'm looking into getting my own plan, which would be considerably cheaper.  And while it looks like basic cleanings and amalgams are covered and resin-based composites are pretty cheap, I'd have to pay a few hundred if I needed an inlay or onlay, crown, etc.  I typically don't have a lot of dental problems so this is a chance I'm willing to take.  

I'm going to call my dentist next week to talk to them, but I wanted to get advice from an outside dentist.  

1. You only need inlays/onlays if you have very big cavitys, correct? Those take two visits, right? Since my cavities are small and the dentist said they shouldn't grow bigger, they probably won't become big enough for an inlay/onlay...?
2. What experience do you have with patiens who have individual dental insurance? I am looking at a dental HMO. Do you find there are hidden fees tacked on or patients end up paying more than if they had better insurance?

[lynn117]

today most dental insurances cover less than previous years. its the same with health insurance. the plan thru your employment is cheaper than what you would pay for yourself because the pay a percentage of the premium so you might get less for the cheaper plan you purchase yourself. most insurances pay around half for a crown or onlay and nothing for an implant. i payed for one recently and it cost with prep and a core $1258 so a couple hundred is very cheap.
two small cavities should be fine waiting a month. inlay/onlays are for teeth with much more serious problems and most fillings last quits awhile and can safely be replaced several times as the degrade. i have been needing crowns for the teeth i have had filled several times for the past 30 + years. fillings dont last forever and even if you provide perfect dental care they get old and need replacement. evert time a filling is replaced the hole needs to be larger until the filling becomes too large and the tooth needs the support of a crown. inlays/onlays cover several teeth at a time and doesnt sound like anything you will need until way in the future if ever.