I have a table with item list inside multicolumns which are not behaving as expected (vertically and horizontally centered):
\newcolumntype{C}{>{\centering\arraybackslash} m{2.3cm}}
\begin{table}
\caption{Some caption}
\label{tab:tab1}
\centering%
\begin{minipage}{\textwidth}
\begin{tabular*}{\textwidth}{|C|C|C|C|>{\centering\arraybackslash}m{3cm}|}
\hline
\ & \textbf{Hellman} & \textbf{Rainbow Table} & \textbf{Proposed Method} & \textbf{Proposed Method with Compression}\\
\hline
Input Range & $2^{37}$ & $2^{37}$ & $2^{37}$ & $2^{37}$ \\ \hline
Size & $1.4$ GB & $1.4$ GB & $1.4$ GB & $1.4$ GB \\ \hline
Hash Operations & $90.3$ M & $7.4$ M & $4$ B & $3.5$ B \\ \hline
Advantages &
\multicolumn{2}{>{\centering\arraybackslash}m{4.9cm}|}{
\begin{itemize}
\item Few hash operations
\end{itemize}
} &
\multicolumn{2}{>{\centering\arraybackslash}m{5.4cm}|}{
\begin{itemize}
\item Little disk access
\item Disk access is serial
\item Success is guaranteed
\item Easily parallelizable
\end{itemize}
} \\
\hline
\end{tabular*}
\end{minipage}
\end{table}
Which results in:
As you can see only the third row (Hash Operations) seem to be precisely centered. The main problem, though, is the last line. The item lists are far from centered in any direction. How can I fix this?
I also don't know why the right side border is not correctly placed but I can manage to get an acceptable result playing with the cell's width (not shown in the image).