It's the big day! You have your forces assembled and painted. After months of painstaking work, you are ready to take the field at your FLGS (Friendly Local Gaming Store) and kick some butt! How are you going to get your stuff there?
Let's talk about transport. You want to be able to transport your miniatures and supplies in a minimum amount of bags and have them arrive to the FLGS (and back home) safely and undamaged. There are several ways to do that.
I suppose the cheapest way of doing that is used egg cartons that your spouse isn't already using. A pistol/rifle case works very well (might attract some attention though), as well as a camera case. All can be used relatively inexpensively and give a moderate level of protection. The problem is a lack of pockets for record sheets, rule books, tape measures, writing instruments, dice and the 15 other items you will need.
There are two bag makers out there that I would recommend. They are Battlefoam, and Sabol Designs. Games Workshop is also a player (#sorrynotsorry for the pun), however I do not consider them flexible enough for what you will be packing, plus they are very proud of their products. GW prices are significantly higher than a comparable product from one of the other mentioned vendors. I will tell you what I did, but you are free to choose your own path. I have purchased from all of these companies but GW. I encourage you to fully explore all of those websites.
Battlefoam: This is a company that makes a quality product. They have semi-hard sided cases that will withstand a lot of abuse and not let your miniatures get hurt. They sell trays with hex-shaped cutouts specifically for Battletech. I have a P.A.C.K. 720 to use for my transport and storage and I couldn't be happier. These are the Large trays, designed to have the P.A.C.K. 720 open with the front facing you and the handle on the top. I use two of the BattleTech Large Foam Tray (BFL) trays (2.5"), two BattleTech Small Foam Tray (BFL) (2") and a generic 1" vehicle tray. This allows me to carry 45 vehicles, 108 regular-sized 'Mechs, 54 larger 'Mechs and 10 of the largest 'Mechs for a total of 217 miniatures, five full IS Battalions with command lances, and leave room for 4 more lances on top of that. The medium trays would stack like an Army Transport, carrying slightly less models. Battlefoam makes pre-made trays for many game systems, plus trays for Games Workshop and Army Transport cases. My forces are expanding to the point I am moving back into a P.A.C.K. 432 I used back when I didn't have as many miniatures. While you could use the large trays from the 720, I recommend the medium trays because using the large trays will have you carrying your miniatures on their side. BFM Large Hex, BFM Small Hex, Vehicle tray and even a tray for the carboard terrain tiles.
Another great feature of the Battlefoam cases is they use the molle system, so you can add a whole bunch of blister packs to hold things not able to be held by the pockets already on the case. And they make custom tray covers too!
Sabol Designs: Sabol are the guys who make the ubiquitous Army Transport. I have a total of 5 Army Transports of various models. I have a Platoon that holds my Epic:Armageddon armies, an original Army Transport, an Army Transport Mark II, and a Army Transport Battalion case that wheels around, that I used to carry my 7,000 points of Ultramarines. My son also uses a Platoon for his Battletech forces. I like the Mark II the best out of all of them because it unzips from the back, making easy access to the trays. It also piggybacks with the Platoon, so one hand can carry multiple bags. While I use the Platoon for my E:A stuff, I don't like it that much, because they made the Platoons just a hair smaller in width and breadth than the other models. Trays are harder to get in and out of that one.When I carried my Battletech models in my Army Transport, I used a third-party vendor (now out of business) that made pre-cut hex trays, but the trays weren't very high quality and I had to glue 1/4" plywood underneith them because the base could not hadle the weight of metal miniatures.
Sabol's trays are not compatible with Battlefoam cases. Sabol also offers pre-cut trays, and can do custom orders, but their bread and butter are the pluck foam trays. My experience with pluck foam is that they fall apart with use, requiring purchasing new trays every 12-14 months because the pluck foam tears away from use.
Games Workshop: They build their cases for their products. GW has zero interest in Battletech. I have never bought any of their cases, I thought they were too overpriced. Your choice.
Load up your forces into their transportation and move out, General!