Yes, your Will is legal wherever it was drawn as long as was properly executed with the appropriate number of witnesses, usually 2.
If you have further questions, contact a local FL lawyer to verify this information.
The answer is a little more complex than whether a will drafted by an attorney in another state is legal in Florida. Yes, a will drawn up in another state executed with all of the formalities required by Florida law will be admitted to probate in Florida. However, there are important state specific estate planning issues that must be considered. An example would be the impact of Florida's Homestead Law on your estate planning. An out of state attorney would not have contemplated what result your will would have if probated in Florida. It's always good to get an attorney's stamp of approval on your estate planning when you move to another state.
Any information contained in the foregoing is not given with the implication that any attorney-client relationship is contemplated or sought.
An out of state will CAN be legal if executed properly in the presence of two witnesses. The difficutly could be if the will was not self-proved, which means the personal representative will need to attempt to locate the witnesses or sign an affidavit that the out of state witnesses are unable to be reached. In addition, laws vary from state to state in particular the Homestead laws. It is always adviseable to have local counsel in your new home state because your out of state attorney cannot practice law in Florida unless he/she is licensed here..