Bulk Heads

As far as bulk heads go, there isn't much that you can do to upgrade them. They hold the front and rear end to the chassis and cant really break unless you crash really hard and manage to snap them off. They are very durable and are at the bottom of your truck so it wont make your truck look bad.

If you want reinforcement, RPM makes a good set of bulkheads that look similar to stock and are built to be more durable. Compared to other bulk heads they are pretty cheap costing around $30 for both.

The other option is the Hot Racing bulk head. It is made out of aluminum and is indestructible. It looks great and cant break off which is a big bonus. The con is that they are expensive coming in at $50 for the front bulk head and $40 for the rear bulk head.

Shock Towers

Shock towers are a very important part of your truck. They play many roles including, holding the roll cage/body mounts, covering part of the diff, holding the front and rear turnbuckles in place, and holding the shocks up. With all of these tasks, the shock towers must be durable and not strip easily.

The first option is RPM. They make a nice durable shock tower out of plastic. The pros are that they work well and cost around $25 for a set which is a pretty decent price. The cons are that they can strip pretty easily because they are made out of plastic. You probably wont lose any parts because they have two connection points but you would have to replace the shock towers more often. 

The second option is to go with an aluminum shock tower like the one that Hot Racing makes. It is lightweight, has a sleek and nice design, is very durable and is made out of aluminum. These come in multiple colors and are much harder to strip than the plastic ones. The suspension will be stiffer because of the lack of flex that plastic has and wont break. On the downside, the Hot Racing shock towers are pretty pricey at around $75 for a set. 

A arms

When choosing your a-arms there are only about 3 options. They are all different, and are all better in different cases. A arms are prone to breaking and bending because of all of the impact they take from jumps and crashes.

The first option is to go with a set of RPM a arms. They are still plastic but are reinforced and have more flex than the stock a arms. These have a lot of slack so they can bend and absorb the force. The pros are that they are only $20 for a set and they are very hard to break. On the down side, when they bend , they cause the steering to change up the angles in the suspension a bit. These are minor things if you plan on bashing a lot, but for racing these are probably not the best. 

The second option is going aluminum. This is a very risky option if you plan on using your car a lot and you expect it to take a beating but is good for light bashing/driving. They are much more durable and stiff so they wont break or bend, this will keep your suspension perfect but there area few cons. They are pretty expensive depending on the ones you go with, between the $50-$80 range. The major problem with them is that there will always be a weak spot in your car, if the a arms are aluminum then all that force is going to go into something else and break it. So now instead of replacing a $5 dollar part. You are now replacing a $50 dollar part.

Last option is the option you should avoid. These are the aluminum a arms that are expensive and very cheap. Avoid these because they are low quality, they will break and bend, and they will empty your wallet. These are company's like Integy and STRC.