Big front mechanical rests are very nice unless you have to travel distance to your matches. Air travel makes those big rests very difficult to move back and forth safely and economically. I have an older Sinclair rest that I used for a while but have since changed over to a good solid bipod. The mechanical rests usually need a few different bags/different heads purchased to fit the different style of stocks on the rifles you use.
Bipods work very well as well if you have a quality made bipod. Bipods are much easier to transport and less likely to be damaged in transit. They are a little different getting used to as some rifles become a little touch sensitive when you attach a bipod to it. I have some rifles like a thin rubber mat under the feet and others that like to slide freely on the shooting bench. You also have to consider the type of stock your rifle has as some like the red wolf (and others) have such a thin forearm on them it makes it tough to mount a UIT rail for the bipod without making the stock less durable. For those types of rifles you can buy other options such as a bottle clamp with a picatinny rail on it or a custom extended picatinny rail that mounts to your action or frame.
Both work well and I use both. I even use a long one piece rest as well for some of my air rifles and rimfire rifles. I would say maybe 80% or higher shooters at EBR this year were using bipods. Podium finishes were a mixture of mechanical rests and (mostly) bipods so one is not more accurate or more robust over the other. Some of my highest scores have come with a bipod but I also still use mechanical rests based on the type of rifle and travel distances. Good quality bipods can be had for approx. $400+. I got my favorite bipod from Europe. Front mechanical rests run from $200 used up to $2000 and one piece rests are approx. $1000 or so. I think one top ten finisher was even using Caldwell tack driver front bag.
Hope this helps you, PM me if you want more info.
P.S. Check out Michaels video at the top of the benchrest page to see the EBR finals competitors and equipment.
Thx
Dan