An initial CHL expires on the license holder's first birthday following the four-year anniversary of the issuance of the license. In other words, an intial license is valid for four (4) years, and in many cases, for some additional months. All renewed licenses are valid for five (5) years.
Yes, online courses are legal and legitimate. GC 411.188 as included in Texas License to Carry and Handgun Laws issued by the Texas Department of Public Safety states (page 17):
What Happens if Your Texas LTC Expires? If your Texas LTC expires, you have one year to renew it. After one year, you must start the application process over again as a new applicant, including taking the required training course.
The firearm must be unloaded. The firearm and any ammunition cannot be readily accessible from the passenger compartment. If the vehicle does not have a separate compartment from the driver's compartment, the firearm must be in a locked container other than the glove compartment or console.
The Texas License to Carry Proficiency Test is not a difficult shooting test to pass. It is a timed test designed with plenty of time to take your shots accurately. You will be shooting at a B-27 target. B27 targets are 24"x45" and come in many colors.
The License to Carry a Handgun service allows you to apply for, renew, or check the status of a handgun license or instructor certification online with the Texas Department of Public Safety.
The LTC is absolutely still worth it in Texas, or really any state with PLC (permitless carry). I am 100% a supporter of PLC, and I am glad that Texas has come on board. It allows anyone who realizes the need to carry for their own protection to immediately start doing it, legally.