This is the thermometer I use and had it for 2 yrs. and if you got amazon prime it's 24.99
https://www.amazon.com/Lavatools-Javelin-Digital-Thermometer-Chipotle/dp/B00GRFHXVQ/ref=sr_1_1/152-9670714-9447101?ie=UTF8&qid=1473802750&sr=8-1&keywords=javelin+thermometer
Me too! My Javelin works great and gives just as quick of a readout as the Thermopens...maybe 1 second longer, but that's it.
And honestly, I'm not sure if the question here is what is your favorite or what is your most used accessory. You can do a lot of different cooking styles with little to no accessories, then as you figure out what kind of cooks you do the most you can upgrade your accessories to match your cook types.
Most Used:Chimney - every single cook
Maverick 733 or my 732 - almost every cook. I even use it for reverse searing. That way I know the temperature of my steaks at all times and don't have to bother with my instant read thermo.
Charcoal baskets - was almost every cook until I got a vortex and slow-n-sear. With baskets you can do most of the things these other accessories do. Once you determine you are going to do a lot of specialize cooking, like slow-n-low smoking, super hot wings, etc, then you can start acquiring the more expensive accessories for these kinds of cooks.
Lighter Cubes - I generally use the gas assist on my performer whether I am using that grill or not, but the cubes are great for when my propane runs out or the performer is already in use and I am firing up a second grill or need to get some coals going to add to an already lit grill.
Weber gourmet grate system - It's heavier duty than the other grate options until you get to the cast iron ones. Allows you to flip up the sides to add more coals, and gives you a lot of fun options for the center.
Favorites: (ordered by frequency of usage)Slow-n-sear - great for reverse searing, indirect cooking, hot and fast cooking, give tons of space for slow-n-low smoking
Kettle Pizza - Once you get this accessory dialed in you will be a pizza cooking fool!!!!
Vortex - Makes really good wings! Baskets do the job almost as well but for the low cost of the vortex it's worth it!
Javelin instant read thermo - I really only use this when I am not using my Maverick. I will use it when smoking larger chunks of meat for checking multiple places even though I have a Maverick probe in the meat already.
Rotisserie - This is probably my least use accessory right now since I mainly use it for whole chickens which I cook 1-2 times a month. Despite limited usage I would not give up my roto!
Other things I have and use a lot:Ove Gloves - The first time you have to remove your cooking great while the grill is hot or warm you will quickly see how a good pair of heat resistant gloves can make life a lot easier. Mine are the mid arm version, so I use them a lot when cooking wings with my vortex so I don't burn all of the hair off of my arms.
IR Thermometer - Quick way to check the temp of my pizza stone, a cast iron skillet, etc.
Maverick Tip Top Temp - this is a newer accessory and I love it. I don't need it and can keep my grill at a consistent slow-n-low temp without it, but it is nice to have it in action and feel like I can leave to run an errand without having to worry about what my grill is doing.
Weber Compact Chimney - I use this to start coals when smoking slow-n-low and only need to light 10-15 coals.