bulpat quickly installs, reinstalls and upgrade-installs sets and clusters of Solaris patches (in any of the four distribution formats), with the same safeguards as the builtin Solaris patch installation utilities.
Yes, you can use it to quickly install or upgrade-install the standard Sun Solaris "recommended patch cluster", as well as any other sets of patches you need.
It can even install patches for unbundled products, such as DiskSuite, SunRay Enterprise Server, SPARCcompiler-C, Sun Internet Mail Server, etc, etc, etc.
It is especially useful for quickly bringing a system up-to-date with a given set of patches, without you having to worry about what patch-state that system is already in, eg: missing some patches, has some superceded or obsoleted patches, has some system-specific additional patches, does not need one of the new patches due to different hardware (x86 versus SPARC, or CG3 graphics versus Elite-3D graphics, etc), patches for uninstalled software components, even patches for alien releases (Solaris 2.5.1 versus Solaris 8, or DiskSuite 3.0.1 versus DiskSuite 4.2, et al).
Of course, it runs very quickly on systems that are already up-to-date, or better!
For all the details, see the manpage.
bulpat has been tested Solaris 2.1, 2.2, 2.3, 2.4, 2.5, 2.5.1, 2.6, 7 and 8, with several combinations of unbundled or third-party software components, and with combinations of the "recommended patch cluster" and sets of additional patches.